How many moles are there in 3.9 grams of potassium

Answer:

solute and solvent

Explanation:

Because solutes dissolves in solvent to form a solution

Answer:

[tex]\boxed {\boxed {\sf About \ 2.96 \ moles \ of \ Argon}}[/tex]

Explanation:

To convert from grams to moles we must use the molar mass, which is found on the Periodic Table.

Use the molar mass as a ratio.

[tex]\frac{39.9 \ g \ Ar}{1 \ mol \ Ar}[/tex]

Multiply by the given number of grams: 118

[tex]118 \ g \ Ar *\frac{39.9 \ g \ Ar}{1 \ mol \ Ar}[/tex]

Flip the fraction so the grams of argon will cancel each other out.

[tex]118 \ g\ Ar * \frac{1 \ mol \ Ar}{39.9 \ g \ Ar}[/tex]

[tex]118 * \frac{ 1 \ mol \ Ar}{39.9 \ g \ Ar}[/tex]

[tex]\frac {118 \ mol \ Ar }{ 39.9 }[/tex]

[tex]2.95739348 \ mol \ Ar[/tex]

The original measurement of grams had 3 significant figures, so our answer must have 3 sig figs.

For the number we calculated, that is the hundredth place. The 7 in the thousandth place tells us to round the 5 to a 6.

[tex]2.96 \ mol \ Ar[/tex]

There are about 2.96 moles of Argon in 118 grams.

Answer:

Fluorine    

Chlorine

Bromine

Iodine

Boiling point increases as you go down the group v11

Explanation:

The elements of Group VII  are the halogens consisting of f fluorine (F), chlorine (Cl), bromine (Br), iodine (I).  All of which are non metals and exists  as diatomic molecules - F2, Cl2, Br2, I2 with  intermolecular attractions between the two molecules of each element held by Van der Waals dispersion force.

Moving down the group, the size of the atoms increases in size from Fluorine, F2 and Chlorine, Cl2 which are gases to Bromine , Br2 which exists as a liquid to solid, Iodine, I2. This attributes to the increasing in Strength of the Van der Waals forces as you go down the group. In order to break the vanderwaals forces , More heat energy is required to change thier states  leading to the increase in  boiling point going down the group.

Fluorine    

Chlorine

Bromine

Iodine

Boiling point increases as you go down the group

A numerical subscript following a set of parentheses represents the number of the group or poly-atomic ion in parentheses are present in a chemical  formula.

As an example, calcium hydroxide is [tex]\bold { Ca(OH)_2 }[/tex] . The subscript (2) indicates that calcium hydroxide contains two hydroxide ions.

Therefore, A numerical subscript following a set of parentheses represents the number of the group or poly-atomic ion in parentheses are present in a chemical  formula.

To know more about Chemical formula

https://brainly.com/question/17429336

Answer:

all element are atom but all at all atom are element

Explanation:

because all atoms of an element are same whereas atom of different element are different

Answer:

Land plants are also known as Embryophytes. Embryophytes are complex multicellular eukaryotes with specialized reproductive organs. The name derives from their innovative characteristic of nurturing the young embryo sporophyte during the early stages of its multicellular development within the tissues of the parent gametophyte.

Explanation:

Answer:

there used for mountains , wait I'm just trynna get points ya feel me

Explanation:

Answer:

Bacteria can evolve quickly because they reproduce at a fast rate.

Explanation:

Bacteria can evolve quickly because they reproduce at a fast rate. Mutations in the DNA of bacteria can produce new characteristics. A random mutation might cause some bacteria to become resistant to certain antibiotics, such as penicillin.

Answer:

The present water by weight for the hydrate = 45.2%

Explanation:

From the given information;

The present water by weight = (weight of the water/ total weight of the hydrate) × 100

The present water by weight = (11.3/25) × 100%

The present water by weight = 0.452 × 100%

The present water by weight for the hydrate = 45.2%

Answer:

nucleus and electrons

Explanation:

nucleus contains protons and neutrons

Answer: equal to

Explanation:

Answer:

c. F

Explanation:

As you go top to bottom down a column of the periodic table, atomic radius increases.

As you go left to right across a period of the periodic table, atomic radius decreases.

Knowing this trend, that means that the smallest atomic radius would be located in the top right of the periodic table. The closest element to that point is fluorine, or answer C.

Answer:

[tex]4dm^{3}[/tex]

Explanation:

1dm^3 is equal to 1L.

Explanation:

Single displacement (replacement) is kind of reaction in which 1 atom of reactants only change in product.

Explanation:

20g of Na and 10g of Cl2 which is in excess?

The equation of the reaction is given as;

2 Na + Cl2  --> 2 NaCl

From the equation;

2 mol of Na reacts with 1 mol of Cl2

Converting the masses of reactants given to mol

Number of moles = Mass / Molar mass

Na;

Number of moles = 20 / 23 = 0.8696 mol

Cl2;

Number of moles = 10 / 71 = 0.1408 mol

In the chemical equation, the ratio was 2: 1 however with the masses, we can tell that Na is in by far excess.

0.8696 mol of Na would require 0.4348 of Cl2 (Present = 0.1408 mol)

This means;

Na - Excess Reactant

Cl2 - Limiting Reactant

Second part; How much NaCl would be produced?

The limiting reactant determines how much of the product is formed.

From the equation of the reactant;

1 mol of Cl2 produces 2 mol of NaCl

0.1408 mol of Cl2 would require x mol of NaCl

1  = 2

0.1408 = x

x = 0.2816 mol of NaCl

Converting to mass;

Mass = Molar Mass * Number of moles

Mass = 58.44 g/mol * 0.2816 mol

Mass = 16.46 g

Answer:

Since hydrogen is the first element, its electron configuration is 1s1.

Explanation:

It has only one electron in its valence shell.

Valence electrons are the outermost electrons or electrons in the largest energy level. Hydrogen has only one electron, so that electron is a valence electron.

Answer:

One valence electron !!

Explanation:

Answer:

c

Explanation:

Answer:

C. electrons. They also have a charge of -1

Answer: Cr2NiO7 is the molecular formula for nickel II dichromate.

Answer:

Alloy

Explanation:

Answer:

these are all types of rocks

sedimentary are formed through the accumalation of different material from earths surface. Like the grand Canyon!

Metamorphic rocks are formed from heat, preasure, or a combination. Found mostly near tectonic plates meet.

Igneous are molten rock.

Explanation:

Sedimentary- a rock that has formed from sediment deposited by water or air

Metamorphic- a rock that has transformed by heat,pressure,or other natural causes

Igneous- a rock that has been solidified by lava or magma

Answer:

Two Electrons.

Explanation:

Strontium is the atom with atomic number 38, and electron configuration is [Kr] 5S^2 which mean just two electrons more than Krypton which one of the Noble gases.

You are looking for an element in the fourth period and a transition metal. As most have about 3 valence electrons. Gallium and Scandium work perfectly.

Answer:

Gallium is the Answer.

Explanation:

Answer:

B

Explanation:

t= 300s has more XY than t=200s, which means that it continues to change

*i think

The system has been predicted to be not possible to reach equilibrium as  changing X and Y concentration. Thus, option B is correct.

Equilibrium has been described as the condition in the reaction mixture, when the concentration of the product and the reactant are equal.

The given reaction has been represented as:

[tex]\rm X+Y\rightarrow\;XY[/tex]

The given reaction has been represented as, with the increase in time, there has been the consumption of the reactant and the formation of product.

The concentration has been continuously changing with time. Thus, the determination of the equilibrium has been difficult with changing X and Y concentration.

Thus, option B is correct.

Learn more about equilibrium concentration, here:

https://brainly.com/question/7949757

Answer:

Biosphere

The Biosphere --contains all the planet's living things. This sphere includes all of the microorganisms, plants, and animals of Earth. Within the biosphere, living things form ecological communities based on the physical surroundings of an area.

Explanation:

Answer:

Biosphere

Explanation:The Biosphere --contains all the planet's living things. This sphere includes all of the microorganisms, plants, and animals of Earth. Within the biosphere, living things form ecological communities based on the physical surroundings of an area. hope this helps (:

Answer:

No of moles = mass in gram / molar mass

Mass in gram = no of moles× molar mass

Mass in gram = 0.6330× 163.94

103.77 gram

Explanation: